Bornean Orangutans in Rapid Decline Despite Conservation Efforts

Jakarta, Indonesia

Things are looking down for Bornean orangutans.

The first ever population trend analysis of Bornean orangutan shows that despite decades of conservation work the species is declining rapidly. In fact, the study indicates that the Bornean orangutan declined at a rate of 25% over the past 10 years.

Such rates of decline were sufficient to elevate the conservation status of this species to Critically Endangered earlier last year. To put the decline in perspective of our own species, we would have lost nearly 2 billion people since 2007, if humans experienced a similar decline. The findings are a major concern for everyone involved with orangutan conservation.

Dr Truly Santika, an Indonesian statistician and researcher at the ARC Centre of Centre for Environmental Decisions (CEED) at UQ lead the paper, said that “our study used advanced modelling techniques that allowed the combination of different survey methods, including helicopter surveys, traditional ground surveys, and interviews with local communities”. “This new approach facilitated the break-through and enable, for the first time, to determine the population trends of the species over time”, said Professor Kerrie Wilson, Director of CEED.

The analyses show that declines are particularly pronounced in West and Central Kalimantan, but even in relatively well protected areas, such as the Malaysian State of Sabah, the rate of decline is still 21.3% (see Figure below).

The study, conducted by a group of some 50 Indonesian, Malaysian, and international researchers, is a wake-up call for the orangutan conservation community and the Indonesian and Malaysian governments who have committed to saving the species. Every year some USD 30-40 million is invested by governmental and non-governmental organizations to halt the decline of wild populations. The study shows that these funds are not effectively spent.

Prof Erik Meijaard, of the University of Queensland, one of the study’s initiators, commented that “the study’s worrying outcomes suggest that we need to fundamentally rethink orangutan conservation strategies. The biggest threats of habitat loss and killing are not effectively addressed, despite government commitments through national action plans. The focus of orangutan conservation is on rescues and rehabilitation, but that only addresses the symptoms and not the underlying problem”.

According to Dr Marc Ancrenaz, a Sabah-based orangutan scientist and contributor to the study, there is hope for orangutans, despite the negative trends that the study demonstrate. “As we learn more about orangutans”, he stated, “we come to understand that the species is ecologically much more versatile than previously thought. Orangutans can survive in multifunctional landscapes, which includes plantations and agricultural lands. But they are very slow breeders and much more needs to be done to reduce killing rates”.

Previous studies have indicated that up to 2,500 orangutans are killed annually on Borneo in conflict situations or by hunters looking for food, and this explains a considerable part of the orangutan’s decline.

“Inappropriate land use planning is another major factor” adds Professor Meijaard. “For example, 10,000 orangutans presently occur in areas that have been allocated by national and local governments to oil palm development. If these areas are converted to oil palm plantations without changes in current practices, most of these 10,000 individuals will be destroyed and the steep population decline is likely to continue in the foreseeable future”.

Ultimately, viable populations of large roaming animals such as the orangutan require a solid network of protected forests that are properly managed, and sustainable practices outside of these protected areas.